noun, often attributive
back·​up | \ ˈbak-ˌəp How to pronounce backup (audio) \

Definition of backup

 (Entry 1 of 2)

1a : one that serves as a substitute or support I brought an extra pencil for backup. a backup plan
b : musical accompaniment The tunes include banjo and guitar backup.
c : additional personnel who provide assistance The police officer called for backup.
2 : an accumulation caused by a stoppage in the flow traffic backup
3 : a copy of computer data (such as a file or the contents of a hard drive) I made a backup copy of the file. also : the act or an instance of making a backup

back up


Definition of back up (Entry 2 of 2)

intransitive verb

: to accumulate in a congested state traffic backed up for miles

transitive verb

1 : to move into a position behind (a teammate) in order to assist on a play
3 : to make a copy of (a computer file or data) to protect against accidental loss or corruption Be sure to back up your work. also : to make copies of all the files on (a device) a program that automatically backs up your hard drive

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Synonyms for backup

Synonyms: Noun

bottleneck, jam, jam-up, logjam, snarl, tailback [British], tie-up

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Examples of backup in a Sentence


His role on the team is to be a backup to the regular quarterback. We have an extra radio as a backup in case this one doesn't work. We have an extra radio for backup. He provides backup for the regular quarterback. She sang backup on his CD.
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Recent Examples on the Web: Noun

No, the phones were ringing off the hook for a career backup who could realistically be described as the worst hitter in more than a century. Jared Diamond, WSJ, "One of the Worst Hitters in Baseball History Is Now a Hot Commodity," 25 Feb. 2019 After all, the only thing more upsetting than this news is the idea of accidentally dropping and shattering your current palette with no backups on hand. Chloe Metzger, Marie Claire, "The Urban Decay Naked Palette Is Officially Being Discontinued," 23 Aug. 2018 In 130 plate appearances, he's been an effective backup, hitting .231 with one homer and 10 extra-base hits. Scott Boeck, USA TODAY, "Dodgers second baseman Chase Utley plans to retire at end of the 2018 season," 13 July 2018 When Daniel was the Chiefs’ backup from 2013-15, Nagy was the quarterbacks coach under head coach Andy Reid. Rich Campbell,, "Mitch Trubisky's ability to command Matt Nagy's offense will define the Bears' season," 11 July 2018 These days Rose is a fairly standard backup, albeit with more explosive potential—and more baggage—than most. Rob Mahoney,, "NBA Free Agency 2018: Under-the-Radar Grades," 4 July 2018 There were some backups, but no crashes at ramps where vehicles were forced to exit I-65 southbound at West 21st Street. Holly V. Hays, Indianapolis Star, "Commuters not bothered by huge I-65 closures," 2 July 2018 Perez's backup, Drew Butera, reached too far on Hammel's first pitch to Tony Kemp with the bases loaded in the second inning. Chandler Rome, Houston Chronicle, "Yuli Gurriel's grand slam fuels Astros' rout of Royals," 24 June 2018 Marciano had called in the maintenance team for backup, not realizing the extent of the danger. Alison Kuznitz,, "'I Had Her Life In My Hands': Spectra Employees Recall Aiding Hartford Officer After Stabbing," 23 June 2018

Recent Examples on the Web: Verb

Rehabilitation refers to things like fixing code violations and bringing the home back up to standards, which in turn, increases the property value. Hadley Mendelsohn, House Beautiful, "No Joke, You Can Buy A House In Indiana For $1," 14 Jan. 2019 Planchet’s second of the game tied it back up for Bromfield 45 seconds later, while Isabelle Katter put her team ahead for good exactly a minute later. Jake Levin,, "Emily Podgorni backstops Bromfield to D2 state final," 21 June 2018 Talk now is of government carrying out a restructuring and putting the airline back up for sale in a year or two. The Economist, "Plans to privatise India’s flag-carrier have run into turbulence," 9 June 2018 Riverdale picks back up new episodes on January 16 on The set your DVR accordingly. Gianluca Russo, Teen Vogue, "Roberto Aguirre-Sacasa Teases Upcoming Episodes of "Riverdale"," 16 Dec. 2018 The public has every reason to be skeptical unless and until Waymo makes an affirmative case—backed up by comprehensive data and independent analysis—that its vehicles are safe. Timothy B. Lee, Ars Technica, "Fully driverless Waymo taxis are due out this year, alarming critics," 1 Oct. 2018 Few investors have backed up bearish views with large negative bets. Laurence Fletcher, WSJ, "Lonely, and Costly, Times for Hedge Funds That Bet on Collapse," 24 Sep. 2018 The lanes were reopened by around 9:30 a.m., but traffic had backed up so much that the average drive time from Everett into Seattle more than doubled, according to the Washington State Department of Transportation. Christine Clarridge, The Seattle Times, "Truck kills person on I-5 near downtown Seattle, snarling traffic for miles," 11 July 2018 Traffic has backed up on the southbound Hardy Toll Road near Aldine Mail Route after a wreck involving a heavy truck. Houston Chronicle, "Wreck shuts down Hardy Toll," 27 June 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'backup.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of backup


1910, in the meaning defined at sense 1a


1801, in the meaning defined at intransitive sense

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Statistics for backup

Last Updated

3 Mar 2019

Look-up Popularity

Time Traveler for backup

The first known use of backup was in 1801

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More Definitions for backup

back up


Financial Definition of back up

What It Is

A back up is an increase in a security’s price, yield, or spread before issuance.

In other circles, back up means replacing a long-maturity security with a short-maturity security in order to capitalize on short-term interest rates that are higher than long-term interest rates.

How It Works

For example, let’s assume that Company XYZ wants to issue $100 million in 10-year bonds. The yields on bonds of similar quality and risk were about 5% when Company XYZ hired the underwriter to handle the bond issue, but since then the required yields have increased to 7%. This means Company XYZ has to issue the bonds at a bigger discount in order to keep the issue competitive, and thus it will obtain less cash from investors at the time of the sale.

This increase in the cost of issuing the securities is a back up.

Why It Matters

Back ups can be very detrimental to issuers, especially if they are relying on a very specific amount of money to come from the issue, and even more especially if the company’s success hinges on the reinvestment of those funds.

Source: Investing Answers



English Language Learners Definition of backup

: a person or thing that can be used to replace or support another person or thing
: help or support provided by additional people or things
US : a situation in which the flow of something (such as traffic) becomes blocked


back·​up | \ ˈbak-ˌəp How to pronounce backup (audio) \

Kids Definition of backup

: a person who takes the place of or supports another The guard called for a backup.

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More from Merriam-Webster on backup

Rhyming Dictionary: Words that rhyme with backup

Thesaurus: All synonyms and antonyms for backup

Spanish Central: Translation of backup

Nglish: Translation of backup for Spanish Speakers

Britannica English: Translation of backup for Arabic Speakers

Comments on backup

What made you want to look up backup? Please tell us where you read or heard it (including the quote, if possible).


to boil down or concentrate

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